1. Field of the Invention
The present invention relates to a joint structure for joining together various panel components and/or rod components for assembling office-use furniture or home-use furniture, such as tables, chairs, shelves, etc. In this specification, panel components and rod components are hereinafter referred to as panel-like components.
2. Description of the Prior Art
Insofar as furniture is concerned, whether it may be office-use furniture or home-use furniture, the so-called "knock-down" type furniture, which is assembled on-site when delivered point rather than when produced, has become increasingly popular in recent years.
A most important point for the knock-down furniture is positioning or location between related parts or components. Furthermore, in assembling the knock-down furniture, an extensive on-site adjustment is substantially impossible. Accordingly, the knock-down furniture must have a simple joint structure which enables easy assembling and be able to retain the necessary post-assembling strength and rigidity.
In view of these requirements, various attempts have been proposed heretofore to provide a joint structure for joining panels of the knock-down furniture. One such prior joint structure is disclosed in U.S. Pat. Nos. 4,883,331 and 4,966,421. The disclosed joint structure includes two dowel holes (matching apertures) formed, for a purpose of positioning, in a mating surface of each of two panels to be connected, one part of a hook-and-loop fastener having a number of male fastener elements or hooks attached to the mating surface of one of the panels over the entire area except a portion defining the dowel holes, and the other part of the hook-and-loop fastener having a number of female fastener flements or loops attached to the mating surface of the other panels over the entire area except a portion defining the dowel holes. In assembling of the panels, the two dowels are fitted in the corresponding pair of confronting dowel holes to position the panels and, at the same time, the two surface-type fastener portions provided on the mating surfaces except the area for the dowel holes are engaged together to connect the panels.
The knock-down furniture is packed in various forms for a purpose of transportation to the assembling site. In order to maintain the handling facility during transportation and the working facility during assembling, the volume of a packed knock-down furniture should preferably be compacted as small as possible. The knock-down furniture is generally packed in such a condition that a plurality of panels are stacked one above another.
According to the joint structure of the panels disclosed in the two U.S. patents specified above, both portions of the hook-and-loop fastener are attached in an exposed condition to the corresponding mating surfaces of the panels. Since the panels are generally packed in a stacked condition as described above, the exposed fastener portions are likely to be subjected to a pressure or compressing force tending to deflect the hooks and loops into a collapsed condition in which instance the fastening ability or strength of the hook-and-loop fastener is considerably reduced. During the assembling work, hooks and/or loops are also susceptible to damage due to interference with other portions with the result that the fastening capability and strength of the hook-and-loop fastener is partly deteriorated.
In the joint structure disclosed in the aforesaid U.S. Patents, the mating surfaces of the panels are not directly engageable with each other because the hook-and-loop fastener is interposed between these two mating surfaces. The thus arranged hook-and-loop fastener deteriorates the appearance of a finished product. Furthermore, due to the elasticity of the hook-and-loop fastener, looseness of joint is unavoidable.
According to the same joint structure, two dowel holes are formed in each of tile mating surfaces of the panels in order to secure the desired positioning and alignment between the mating surfaces. However, since the dowel holes and the dowels engaged therein are both circular in cross section, if two or more dowel holes cannot be formed in the joint structure for some reasons, for instance when a leg of a table is to be attached to a top plate of the table by means of a single dowel engageable with a pair of aligned dowel holes formed in the top face of the leg and the backside of the top plate, the leg is likely to be attached in a misaligned condition relative to the top plate, thus requiring an adjustment which is tedious and time-consuming.